Tube cutter capable of cutting tubes with various diameters

1. A tube cutter, comprising:

a main device including a fixed member and a movable member, wherein the movable member is movably connected to the fixed member, and a cutting space is formed between the fixed member and the movable member;

a blade, which is fixed to the main device, having a blade portion in the cutting space; and

a controller provided on the main device to be operated to move the movable member for changing a size of the cutting space;

wherein the controller has a cam pivoted on the fixed member so that the cam is turnable, and the cam has a first cam face and a second cam face; the movable member has a resting portion to rest against the first cam face or the second cam face of the cam when the cam is turned to move the movable member;

wherein the controller further includes an elastic member, and the elastic member urges the movable member to press the resting portion thereof on the cam;

wherein the elastic member has two coil portions and a connecting portion with opposite ends connected to the coil portion; an axle passes through the fixed member and the coil portions; the elastic member is connected to the fixed member with the connecting portion against the movable member.

2. The tube cutter of claim 1 , wherein the fixed member is provided with a receiving room, in which a portion of the movable member is received, and a first connector is provided to pivot the movable member on the fixed member.

3. A tube cutter, comprising:

a main device including a fixed member and a movable member, wherein the movable member is movably connected to the fixed member, and a cutting space is formed between the fixed member and the movable member;

a blade, which is fixed to the main device, having a blade portion in the cutting space; and

a controller provided on the main device to be operated to move the movable member for changing a size of the cutting space;

wherein the controller has a cam pivoted on the fixed member so that the cam is turnable, and the cam has a first cam face and a second cam face; the movable member has a resting portion to rest against the first cam face or the second cam face of the cam when the cam is turned to move the movable member;

wherein the controller further has an arm; the arm is pivoted on the fixed member; the arm has a guiding slot; a guider is inserted into the guiding slot of the arm and connected to the movable member, whereby the guider moves in the guiding slot when the movable member is moved relative to the fixed member.

4. A tube cutter, comprising:

a main device including a fixed member and a movable member, wherein the movable member is movably connected to the fixed member, and a cutting space is formed between the fixed member and the movable member;

a blade, which is fixed to the main device, having a blade portion in the cutting space; and

a controller provided on the main device to be operated to move the movable member for changing a size of the cutting space;

wherein the controller has a cam pivoted on the fixed member so that the cam is turnable, and the cam has a first cam face and a second cam face; the movable member has a resting portion to rest against the first cam face or the second cam face of the cam when the cam is turned to move the movable member;

wherein the controller further has two arms and a pipe; the arms are pivoted on the fixed member, and the pipe is provided between the arms; each of the arms has a guiding slot; an axle passes through the fixed member, the arms and the pipe; two guiders are inserted into the guiding slots of the arms respectively and connected to the movable member, whereby the guiders move in the guiding slots when the movable member is moved relative to the fixed member.

5. The tube cutter of claim 1 , wherein the controller further includes a knob connected to the cam to be operated by a user.

6. The tube cutter of claim 1 , wherein the blade has a portion embedded in the fixed member, and the blade portion is projected from a surface of the fixed member.

7. The tube cutter of claim 1 , wherein the cam further has a third cam face to rest against the resting portion of the movable member when the cam is turned to a specified position.